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Li S, Xu W, Lin M, Lu Z, Ma Z, Chen S, Yang Y, Zhang H. Heat Resistance, Virulence, and Gene Expression of Desiccation-Adapted Salmonella Enteritidis During Long-Term Storage in Low-Water Activity Foods. Foodborne Pathog Dis 2024; 21:119-126. [PMID: 38010814 DOI: 10.1089/fpd.2023.0101] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2023] Open
Abstract
Desiccation stress could induce crossprotection and even affect virulence of Salmonella enterica. However, the influence of food matrices with low-water activity on desiccation adaptation of Salmonella still remains unclear. This study investigated the survival and adaptation of Salmonella Enteritidis in skim milk powder, ginger powder, and chocolate powder under desiccation storage conditions for a total of 12 weeks. High survival rates of Salmonella Enteritidis in all food matrices maintained over the long-term desiccation storage. Desiccation-adapted Salmonella Enteritidis enhanced heat resistance (p < 0.05) with the increase of storage time. Food composition plays an important role in the induction of crossresistance of desiccation-adapted Salmonella. After desiccation storage, Salmonella Enteritidis in ginger powder was most tolerant to heat treatment. Salmonella Enteritidis in skim milk powder was most resistant to the gastrointestinal simulation environment, and had strongest adhesion to Caco-2 cells. The effects of food composition on gene expression (rpoS, proV, otsA, otsB, grpE, dnaK, rpoH, and sigDE) in desiccation-adapted Salmonella Enteritidis were not significant (p > 0.05). At initial desiccation storage, osmotic protection-related genes (fadA, proV, otsA, and otsB), stress response regulator (rpoS), and heat-resistance-related genes (grpE, dnaK, and rpoH) were all significantly upregulated (p < 0.05). However, after 4-week storage, the expression level of desiccation-related genes, proV, otsA, otsB, grpE, dnaK, and rpoH, significantly decreased (p < 0.05). This study enables a better understanding of Salmonella's responses to long-term desiccation stress in different kinds of low-water activity foods.
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Affiliation(s)
- Shaoting Li
- Department of Biological Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, China
| | - Weiying Xu
- Department of Biological Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, China
| | - Mengzhe Lin
- Department of Biological Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, China
| | - Ziying Lu
- Department of Biological Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, China
| | - Zhuolin Ma
- Department of Biological Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, China
| | - Siyi Chen
- Department of Biological Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, China
| | - Yuheng Yang
- Department of Biological Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, China
| | - Hongmei Zhang
- Department of Biological Engineering, School of Biomedical and Pharmaceutical Sciences, Guangdong University of Technology, Guangzhou, China
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Minor M, Sabillón L. Effectiveness of Ultra-High Irradiance Blue-Light-Emitting Diodes to Control Salmonella Contamination Adhered to Dry Stainless Steel Surfaces. Microorganisms 2024; 12:103. [PMID: 38257930 PMCID: PMC10819507 DOI: 10.3390/microorganisms12010103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2023] [Revised: 01/01/2024] [Accepted: 01/03/2024] [Indexed: 01/24/2024] Open
Abstract
Controlling Salmonella contamination in dry food processing environments represents a significant challenge due to their tolerance to desiccation stress and enhanced thermal resistance. Blue light is emerging as a safer alternative to UV irradiation for surface decontamination. In the present study, the antimicrobial efficacy of ultra-high irradiance (UHI) blue light, generated by light-emitting diodes (LEDs) at wavelengths of 405 nm (841.6 mW/cm2) and 460 nm (614.9 mW/cm2), was evaluated against a five-serovar cocktail of Salmonella enterica dry cells on clean and soiled stainless steel (SS) surfaces. Inoculated coupons were subjected to blue light irradiation treatments at equivalent energy doses ranging from 221 to 1106 J/cm2. Wheat flour was used as a model food soil system. To determine the bactericidal mechanisms of blue light, the intracellular concentration of reactive oxygen species (ROS) in Salmonella cells and the temperature changes on SS surfaces were also measured. The treatment energy dose had a significant effect on Salmonella inactivation levels. On clean SS surfaces, the reduction in Salmonella counts ranged from 0.8 to 7.4 log CFU/cm2, while, on soiled coupons, the inactivation levels varied from 1.2 to 4.2 log CFU/cm2. Blue LED treatments triggered a significant generation of ROS within Salmonella cells, as well as a substantial temperature increase in SS surfaces. However, in the presence of organic matter, the oxidative stress in Salmonella cells declined significantly, and treatments with higher energy doses (>700 J/cm2) were required to uphold the antimicrobial effectiveness observed on clean SS. The mechanism of the bactericidal effect of UHI blue LED treatments is likely to be a combination of photothermal and photochemical effects. These results indicate that LEDs emitting UHI blue light could represent a novel cost- and time-effective alternative for controlling microbial contamination in dry food processing environments.
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Affiliation(s)
- Martha Minor
- Department of Family & Consumer Sciences, New Mexico State University, Las Cruces, NM 88003, USA
| | - Luis Sabillón
- Department of Family & Consumer Sciences, New Mexico State University, Las Cruces, NM 88003, USA
- Center of Excellence in Sustainable Food and Agricultural Systems, New Mexico State University, Las Cruces, NM 88003, USA
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Hugho EA, Kumburu HH, Thomas K, Lukambagire AS, Wadugu B, Amani N, Kinabo G, Hald T, Mmbaga BT. High diversity of Salmonella spp. from children with diarrhea, food, and environmental sources in Kilimanjaro - Tanzania: one health approach. Front Microbiol 2024; 14:1277019. [PMID: 38235427 PMCID: PMC10793262 DOI: 10.3389/fmicb.2023.1277019] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Accepted: 12/06/2023] [Indexed: 01/19/2024] Open
Abstract
Salmonella is one of the most frequent causes of diarrhea globally. This study used a One Health approach to identify Salmonella species in children admitted with diarrhea and tested samples from the cases' household environment to investigate their genetic similarity using whole genome sequencing. Surveillance of hospitalized diarrhea cases among children under 5 years was conducted in rural and urban Moshi Districts in the Kilimanjaro Region of Tanzania from July 2020 through November 2022. Household visits were conducted for every child case whose parent/caregiver provided consent. Stool samples, water, domestic animal feces, meat, and milk were collected and tested for Salmonella. Isolates were sequenced on the Illumina NextSeq platform. Multilocus Sequence Typing and phylogenetic analyses were performed to map the genetic relatedness of the isolates. Salmonella was isolated from 72 (6.0%) of 1,191 samples. The prevalence of Salmonella in children with diarrhea, domestic animal feces, food, and water was 2.6% (n = 8/306), 4.6% (n = 8/174), 4.2% (n = 16/382), and 17.3% (n = 39/225), respectively. Four (1.3%) of the 306 enrolled children had a Salmonella positive sample taken from their household. The common sequence types (STs) were ST1208, ST309, ST166, and ST473. Salmonella Newport was shared by a case and a raw milk sample taken from the same household. The study revealed a high diversity of Salmonella spp., however, we detected a Salmonella clone of ST1208 isolated at least from all types of samples. These findings contribute to understanding the epidemiology of Salmonella in the region and provide insight into potential control of foodborne diseases through a One Health approach.
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Affiliation(s)
- Ephrasia A. Hugho
- Biotechnology Research Laboratory, Kilimanjaro Clinical Research Institute, Moshi, Kilimanjaro, Tanzania
- Institute of Public Health, Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - Happiness H. Kumburu
- Biotechnology Research Laboratory, Kilimanjaro Clinical Research Institute, Moshi, Kilimanjaro, Tanzania
- Department of Biochemistry, Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - Kate Thomas
- Ministry of Primary Industries, New Zealand Food Safety, Wellington, New Zealand
| | | | - Boaz Wadugu
- Biotechnology Research Laboratory, Kilimanjaro Clinical Research Institute, Moshi, Kilimanjaro, Tanzania
| | - Nelson Amani
- Biotechnology Research Laboratory, Kilimanjaro Clinical Research Institute, Moshi, Kilimanjaro, Tanzania
| | - Grace Kinabo
- Biotechnology Research Laboratory, Kilimanjaro Clinical Research Institute, Moshi, Kilimanjaro, Tanzania
- Department of Pediatrics, Christian Medical Center, Kilimanjaro, Moshi, Tanzania
- Faculty of Medicine, Kilimanjaro Christian Medical University College, Moshi, Tanzania
| | - Tine Hald
- Research Group for Genomic Epidemiology, Technical University of Denmark, Lyngby, Denmark
| | - Blandina T. Mmbaga
- Biotechnology Research Laboratory, Kilimanjaro Clinical Research Institute, Moshi, Kilimanjaro, Tanzania
- Department of Pediatrics, Christian Medical Center, Kilimanjaro, Moshi, Tanzania
- Faculty of Medicine, Kilimanjaro Christian Medical University College, Moshi, Tanzania
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Manyi-Loh CE, Lues R. A South African Perspective on the Microbiological and Chemical Quality of Meat: Plausible Public Health Implications. Microorganisms 2023; 11:2484. [PMID: 37894142 PMCID: PMC10608972 DOI: 10.3390/microorganisms11102484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 09/06/2023] [Accepted: 09/20/2023] [Indexed: 10/29/2023] Open
Abstract
Meat comprises proteins, fats, vitamins, and trace elements, essential nutrients for the growth and development of the body. The increased demand for meat necessitates the use of antibiotics in intensive farming to sustain and raise productivity. However, the high water activity, the neutral pH, and the high protein content of meat create a favourable milieu for the growth and the persistence of bacteria. Meat serves as a portal for the spread of foodborne diseases. This occurs because of contamination. This review presents information on animal farming in South Africa, the microbial and chemical contamination of meat, and the consequential effects on public health. In South Africa, the sales of meat can be operated both formally and informally. Meat becomes exposed to contamination with different categories of microbes, originating from varying sources during preparation, processing, packaging, storage, and serving to consumers. Apparently, meat harbours diverse pathogenic microorganisms and antibiotic residues alongside the occurrence of drug resistance in zoonotic pathogens, due to the improper use of antibiotics during farming. Different findings obtained across the country showed variations in prevalence of bacteria and multidrug-resistant bacteria studied, which could be explained by the differences in the manufacturer practices, handling processes from producers to consumers, and the success of the hygienic measures employed during production. Furthermore, variation in the socioeconomic and political factors and differences in bacterial strains, geographical area, time, climatic factors, etc. could be responsible for the discrepancy in the level of antibiotic resistance between the provinces. Bacteria identified in meat including Escherichia coli, Listeria monocytogenes, Staphylococcus aureus, Campylobacter spp., Salmonella spp., etc. are incriminated as pathogenic agents causing serious infections in human and their drug-resistant counterparts can cause prolonged infection plus long hospital stays, increased mortality and morbidity as well as huge socioeconomic burden and even death. Therefore, uncooked meat or improperly cooked meat consumed by the population serves as a risk to human health.
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Affiliation(s)
- Christy E. Manyi-Loh
- Centre of Applied Food Sustainability and Biotechnology, Central University of Technology, Bloemfontein 9301, South Africa;
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Mkangara M. Prevention and Control of Human Salmonella enterica Infections: An Implication in Food Safety. INTERNATIONAL JOURNAL OF FOOD SCIENCE 2023; 2023:8899596. [PMID: 37727836 PMCID: PMC10506869 DOI: 10.1155/2023/8899596] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2022] [Revised: 08/19/2023] [Accepted: 08/26/2023] [Indexed: 09/21/2023]
Abstract
Salmonella is a foodborne zoonotic pathogen causing diarrhoeal disease to humans after consuming contaminated water, animal, and plant products. The bacterium is the third leading cause of human death among diarrhoeal diseases worldwide. Therefore, human salmonellosis is of public health concern demanding integrated interventions against the causative agent, Salmonella enterica. The prevention of salmonellosis in humans is intricate due to several factors, including an immune-stable individual infected with S. enterica continuing to shed live bacteria without showing any clinical signs. Similarly, the asymptomatic Salmonella animals are the source of salmonellosis in humans after consuming contaminated food products. Furthermore, the contaminated products of plant and animal origin are a menace in food industries due to Salmonella biofilms, which enhance colonization, persistence, and survival of bacteria on equipment. The contaminated food products resulting from bacteria on equipment offset the economic competition of food industries and partner institutions in international business. The most worldwide prevalent broad-range Salmonella serovars affecting humans are Salmonella Typhimurium and Salmonella Enteritidis, and poultry products, among others, are the primary source of infection. The broader range of Salmonella serovars creates concern over multiple strategies for preventing and controlling Salmonella contamination in foods to enhance food safety for humans. Among the strategies for preventing and controlling Salmonella spread in animal and plant products include biosecurity measures, isolation and quarantine, epidemiological surveillance, farming systems, herbs and spices, and vaccination. Other measures are the application of phages, probiotics, prebiotics, and nanoparticles reduced and capped with antimicrobial agents. Therefore, Salmonella-free products, such as beef, pork, poultry meat, eggs, milk, and plant foods, such as vegetables and fruits, will prevent humans from Salmonella infection. This review explains Salmonella infection in humans caused by consuming contaminated foods and the interventions against Salmonella contamination in foods to enhance food safety and quality for humans.
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Affiliation(s)
- Mwanaisha Mkangara
- Department of Science and Laboratory Technology, Dar es Salaam Institute of Technology, P.O. Box 2958, Dar es Salaam, Tanzania
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Pereira JAM, Berenguer CV, Câmara JS. Delving into Agri-Food Waste Composition for Antibacterial Phytochemicals. Metabolites 2023; 13:metabo13050634. [PMID: 37233675 DOI: 10.3390/metabo13050634] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2023] [Revised: 04/20/2023] [Accepted: 05/06/2023] [Indexed: 05/27/2023] Open
Abstract
The overuse of antibiotics in the healthcare, veterinary, and agricultural industries has led to the development of antimicrobial resistance (AMR), resulting in significant economic losses worldwide and a growing healthcare problem that urgently needs to be solved. Plants produce a variety of secondary metabolites, making them an area of interest in the search for new phytochemicals to cope with AMR. A great part of agri-food waste is of plant origin, constituting a promising source of valuable compounds with different bioactivities, including those against antimicrobial resistance. Many types of phytochemicals, such as carotenoids, tocopherols, glucosinolates, and phenolic compounds, are widely present in plant by-products, such as citrus peels, tomato waste, and wine pomace. Unveiling these and other bioactive compounds is therefore very relevant and could be an important and sustainable form of agri-food waste valorisation, adding profit for local economies and mitigating the negative impact of these wastes' decomposition on the environment. This review will focus on the potential of agri-food waste from a plant origin as a source of phytochemicals with antibacterial activity for global health benefits against AMR.
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Affiliation(s)
- Jorge A M Pereira
- CQM-Centro de Química da Madeira, Campus da Penteada, Universidade da Madeira, 9020-105 Funchal, Portugal
| | - Cristina V Berenguer
- CQM-Centro de Química da Madeira, Campus da Penteada, Universidade da Madeira, 9020-105 Funchal, Portugal
| | - José S Câmara
- CQM-Centro de Química da Madeira, Campus da Penteada, Universidade da Madeira, 9020-105 Funchal, Portugal
- Departamento de Química, Faculdade de Ciências Exatas e da Engenharia, Campus da Penteada, Universidade da Madeira, 9020-105 Funchal, Portugal
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Li S, Chen Y, Zeng J, Zeng H, Ma Z, Chen S, Yang Y, Zhang H. Metabolomics-based response of Salmonella to desiccation stress and skimmed milk powder storage. Front Microbiol 2023; 14:1092435. [PMID: 36910198 PMCID: PMC9996163 DOI: 10.3389/fmicb.2023.1092435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2022] [Accepted: 02/03/2023] [Indexed: 02/25/2023] Open
Abstract
The strong survival ability of Salmonella in low-moisture foods (LMFs) has been of public concern, and is considered a threat to people's health. Recently, the development of omics technology has promoted research on the molecular mechanisms of the desiccation stress response of pathogenic bacteria. However, multiple analytical aspects related to their physiological characteristics remain unclear. We explored the physiological metabolism changes of S. enterica Enteritidis exposed to a 24 h-desiccation treatment and a subsequent 3-month desiccation storage in skimmed milk powder (SMP) with an approach of gas chromatography-mass spectrometry (GC-MS) and ultra-performance liquid chromatography-Q Exactive-mass spectrometry (UPLC-QE-MS). A total of 8,292 peaks were extracted, of which 381 were detected by GC-MS and 7,911 peaks were identified by LC-MS/MS, respectively. Through analyses of differentially expressed metabolites (DEMs) and key pathways, a total of 58 DEMs emerged from the 24 h-desiccation treatment, which exhibited the highest relevance for five metabolic pathways, involving glycine, serine, and threonine metabolism, pyrimidine metabolism, purine metabolism, vitamin B6 metabolism, and pentose phosphate pathway. After 3-month SMP storage, 120 DEMs were identified, which were related to several regulatory pathways including arginine and proline metabolism, serine and threonine metabolism, β-alanine metabolism, glycerolipid metabolism, and glycolysis. The analyses of key enzyme activities of XOD, PK, and G6PDH and ATP content provided further evidence that supported the metabolic responses such as nucleic acid degradation, glycolysis, and ATP production played an important role in Salmonella's adaptation to desiccation stress. This study enables a better understanding of metabolomics-based responses of Salmonella at the initial stage of desiccation stress and the following long-term adaptive stage. Meanwhile, the identified discriminative metabolic pathways may serve as potentially useful targets in developing strategies for the control and prevention of desiccation-adapted Salmonella in LMFs.
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Affiliation(s)
- Shaoting Li
- College of Biological and Pharmaceutical Science, Guangdong University of Technology, Guangzhou, China
| | - Yingqi Chen
- College of Biological and Pharmaceutical Science, Guangdong University of Technology, Guangzhou, China
| | - Ji Zeng
- College of Biological and Pharmaceutical Science, Guangdong University of Technology, Guangzhou, China
| | - Haiyan Zeng
- College of Biological and Pharmaceutical Science, Guangdong University of Technology, Guangzhou, China
| | - Zhuolin Ma
- College of Biological and Pharmaceutical Science, Guangdong University of Technology, Guangzhou, China
| | - Siyi Chen
- College of Biological and Pharmaceutical Science, Guangdong University of Technology, Guangzhou, China
| | - Yuheng Yang
- College of Biological and Pharmaceutical Science, Guangdong University of Technology, Guangzhou, China
| | - Hongmei Zhang
- College of Biological and Pharmaceutical Science, Guangdong University of Technology, Guangzhou, China
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Lee JI, Kim SS, Kang DH. Stress response of Salmonella Montevideo adapted to red pepper powders at various humidities and resistance to near-infrared heating. Food Res Int 2022; 162:111972. [DOI: 10.1016/j.foodres.2022.111972] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 09/18/2022] [Accepted: 09/21/2022] [Indexed: 11/04/2022]
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Chick M, Lourenco A, Maserati A, Fink RC, Diez-Gonzalez F. Thermal Death Kinetics of Three Representative Salmonella enterica Strains in Toasted Oats Cereal. Microorganisms 2022; 10:1570. [PMID: 36013988 PMCID: PMC9416204 DOI: 10.3390/microorganisms10081570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2022] [Accepted: 08/01/2022] [Indexed: 11/16/2022] Open
Abstract
Several reports have indicated that the thermal tolerance of Salmonella at low-water activity increases significantly, but information on the impact of diverse food matrices is still scarce. The goal of this research was to determine the kinetic parameters (decimal reduction time, D; time required for the first decimal reduction, δ) of thermal resistance of Salmonella in a previously cooked low water activity food. Commercial toasted oats cereal (TOC) was used as the food model, with or without sucrose (25%) addition. TOC samples were inoculated with 108 CFU/mL of a single strain of one of three Salmonella serovars (Agona, Tennessee, Typhimurium). TOC samples were ground and equilibrated to aw values of 0.11, 0.33 and 0.53, respectively. Ground TOC was heated at temperatures between 65 °C and 105 °C and viable counts were determined over time (depending on the temperature for up to 6 h). Death kinetic parameters were determined using linear and Weibull regression models. More than 70% of Weibull's adjusted regression coefficients (Radj2) and only 38% of the linear model's Radj2 had values greater than 0.8. For all serovars, both D and δ values increased consistently at a 0.11 aw compared to 0.33 and 0.53. At 0.33 aw, the δ values for Typhimurium, Tennessee and Agona were 0.55, 1.01 and 2.87, respectively, at 85 °C, but these values increased to 65, 105 and 64 min, respectively, at 0.11 aw. At 100 °C, δ values were 0.9, 5.5 and 2.3 min, respectively, at 0.11 aw. The addition of sucrose resulted in a consistent reduction of eight out of nine δ values determined at 0.11 aw at 85, 95 and 100 °C, but this trend was not consistent at 0.33 and 0.53 aw. The Z values (increase of temperature required to decrease δ-value one log) were determined with modified δ values for a fixed β (a fitting parameter that describes the shape of the curve), and ranged between 8.9 °C and 13.4 °C; they were not influenced by aw, strain or sugar content. These findings indicated that in TOC, high thermal tolerance was consistent among serovars and thermal tolerance was inversely dependent on aw.
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Affiliation(s)
- Matthew Chick
- Department of Food Science and Nutrition, University of Minnesota, Saint Paul, MN 55455, USA
| | - Antonio Lourenco
- Food Biosciences Department, Teagasc Food Research Centre, Moorepark, P61 C996 Fermoy, Ireland
| | - Alice Maserati
- Department of Food Science and Nutrition, University of Minnesota, Saint Paul, MN 55455, USA
| | - Ryan C. Fink
- Faculty of Computer Science, Dalhousie University, Halifax, NS B3H 4R2, Canada
- Institute for Comparative Genomics, Dalhousie University, Halifax, NS B3H 4R2, Canada
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